Q value of a nuclear reactions is positive . The reaction is

Options

A. Exothermic
B. Endothermic
C. Elastic
D. Both exothermic and endothermic

Answer

To determine the nature of the nuclear reaction based on the Q value, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Q Value**: The Q value of a nuclear reaction indicates the net energy change during the reaction. A positive Q value means that energy is released during the reaction.

2. **Writing a General Reaction**: Consider a general nuclear reaction represented as:
\[ A + B \rightarrow C + Q \]
Here, \(A\) and \(B\) are the reactants, \(C\) is the product, and \(Q\) represents the energy released.

3. **Identifying Energy Release**: Since the Q value is positive, it indicates that energy is released when the reactants \(A\) and \(B\) transform into product \(C\).

4. **Classifying the Reaction**: In thermodynamics, reactions can be classified as:
- **Exothermic**: Reactions that release energy (positive Q value).
- **Endothermic**: Reactions that absorb energy (negative Q value).

5. **Conclusion**: Since the Q value is positive, the reaction is classified as **exothermic**. This means that energy is released into the surroundings during the reaction.

### Final Answer:
The reaction is **exothermic**.

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